Poly-β-hydroxybutyrate（PHB）has good biological compatibility and biodegradable properties, and is mainly produced by the cell fermentation. The main synthesis methods are genetic engineering bacteria fermentation production, plant production, activated sludge engineering production method, etc. Commonly used extraction methods include solvent extraction method, chemical reagent method, enzymatic, etc. The main modification methods are copolymeri-zation modified, with nano materials modified as well as with other polymer blending modification and so on. The main research directions of Poly-β-hydroxybutyrate（PHB）in the future are screening and constructing high yield strains, optimizing the extraction technology and deepen the modification research.